Draft-indicator for locomotives.



Patented Aug. 29.. |899.

J; E. RANKINE. DRAFT INDICATOR FOR LUCOMOTIVES.

(Application filed. Apr. 14. 189B.)

(No Model.)

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cams Przns co.. Pnmaumo., wnsmnmou o c JAMES EARIIE RANKINE, OE ELKRAPIDS, MICHIGAN.

DRAFT-INDICATOR FOR LOCOh/IOTIVES.

SPECIFICATION forming part of Letters Patent No. 632,203, dated August29, 1899. Application filed April 14, 1898. Serial No. 677,614. (Nomodel.)

To all whon t may 0072/007071,.-

Beitknown that I, J AMES EARLE RANKINE, a citizen of the United States,residing at Elk Rapids, in the county of Antrim and State of Michigan,have invented certain new and useful Improvements in Exhaust Mechanism;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to exhaust mechanism for engines, beingparticularly designed for use in connection with locomotive-engines.

The object of the present invention is to provide what may be termed avisual draftgage7 for the purpose ofindieatin g the amount of draft inthe fire-box.

It is well known that in locomotives it is sometimes required to largelyincrease the power for a short period of time, and when the steam-poweris increased the exhauststeam is of necessity caused to pass through thecontracted exhaust-nozzle, thereby greatly increasing the draft throughthe furnace, which has a tendency to break up or disintegrate the tire,ofttimes throwing red-hot coke from the stack, which is a source ofconsiderable danger to contiguous property. N umerous expedients havebeen devised to overcome this difficulty, but in most instances thedevices have been placed within the stack or inside of the smoke-arch,Where they were subjected to the hot gases and in a short time rendereduseless.

It is the object of this invention to provide means under the readycontrol of the engineer whereby the exhaust may be increased ordiminished at pleasure, and in connection with this a draft-gage isemployed by which the amount of draft is visually indicated, thusenabling the engineer to divert as large a quantity of the exhaust-steamfrom the ordinary exhaust-nozzle as may be necessary to prevent thebreaking up of the fire.

The invention consists in certain novel features and details ofconstruction and arrangement of parts, as hereinafter fully described,illustrated in the drawings, and incorporated in the claims.

In the accompanying drawings, Figure 1 is a sectional View of adraft-gage constructed in accordance with the present invention. Fig. 2is a diagrammatic View, in partial section, of a locomotive boiler andcab, showing the manner of applying the improved gage thereto.

Similar numerals of reference designate corresponding' parts in bothfigures.

In carrying out the present invention I employ a draft-indicator gage,which is in the form of a transparent tube (indicated at 1) bent in Ushape to comprise two legs 2 and 3, the bend or curve 4 in the gagebeing at the lowermost point and the legs 2 and 3 extending upwardtherefrom. Hthin this gagetube is placed a quantity of water or otherliquid having the same or a less specific gravity.

The tubular gage 1 is mounted by means of one or more clips or brackets5 upon a supporting block or base G, and conneetedalso to said block orbase is a valve-chamber 7, having a door S for affording access thereto.In one side of the yalve-casing7 is an opening 9, from which a tubularconnection 10 extends to and communicates with one of the legs 3 of thedraft-gage. Vithin the casing 7 is a fiat or iiap valve 11, suspended bya strap 12 and resting lightly over the opening 9 leading to the pipe10. Communicating with the valve-chamber 7 isa pipe 13, which extendsdownward into and communicates with the tire-box, so that the aircontained therein may be influenced by any partial vacuum which occursin the fire-box due to the forcing of the exhaust-steam outward throughthe stack.

The parts above enumerated are located wi thin the cab under the eye ofthe engineer, Whocan by glancing at the indicator 1, which is graduatedexteriorly, note the level of the liquid in the leg 3 of the gage, andthereby ascertain the amount of draft.

14 designates the discharge-nozzle for the exhaust-steam, which isprovided with a contracted discharge end 15, arranged at or near thebase of the st-ack 16. It will be understood that the discharge-nozzle14 communi- Cates with the exhaust orifices or ports in thesteam-cylinders.

Extending laterally froi'n the nozzle 14 is a branch nozzle 17, whichyextends through the shell and outward at one side of the stack.

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Within said branch nozzle 17 is arranged a valve 18, which is mountedupon a central stem 19, which forms the pivot upon which the valvemoves. Connected to the stem of the valve is an arm 20, and connected tosaid arm is a contractile spring, attached at its opposite end to afixed point, the tension of said spring being exerted to hold the valveclosed or in a position in which it willV obstruct the outward passageof exhaust-steam. By having the valve pvoted centrally and diametricallythe pressure of the exhauststeam is equal on both sides of the fulcrum,and therefore there is little tendency to open the valve, and suchtendency is overcome by means of the spring 21. An operating-rod 22 isconnected at one end to the arm 2() on the stem of the valve and passesrearward through and into the cab, where it is provided with a handle23, by grasping'which the engineer may open or close the valve 1S to thedesired extent. In connection with the rod 22 any suitable means may beused for holding the rod at any point of adjustment, thereby holding thevalve entirely closed or open or at any intermediate point.

From the foregoing description the operation of the device will beunderstood. The exhaust-steam passing out through the nozzle 15 causes asuction through the fire-tubes of the boiler and promotes draft in thefire-box. This is productive of a partial vacuum in the ire-box,and suchpartial Vacuum sucks the air through the tube 13 from the valvechamber7, thus opening the valve 11 and causing also a partial vacuum in thetube 10 and leg 3 of the draft-gage. This causes the liquid in the leg 3to rise, and the greater the draft, and consequently the greater thevacuum produced in the fire-box, the higher will the liquid rise withinthe gage. In case the draft becomes too great the' engineer by operatingthe rod 22 may open the valve 18 to any desired extent, thus permittinga corresponding amount of the exhaust-steam to pass out through thebranch nozzle 17 directly to the atmosphere Without passing upwardthrough the stack, and thereby increasing the draft. In other words, thegage 1 indicates the amount of draft, and the engineer, by means of therod 22, may set the valve so as to reduce the draft to any desiredextent. The object in providing the valve 11 is to overcome thepulsations in the draft-gage due to and caused by the intermittentexhaust of the steam through the discharge-nozzle at the base of thestack, the said valve 11 keeping up a constant Vibration as it isinfluenced by the intermittent action of the exhaust-steam andpreventing the communication of such action of the steam to the liquidcontained in the gage, but when the engine is stopped will leaksufficient to bring the gage to zero in about fifteen seconds.

Having thus described the invention, what is claimed as new, and desiredto be secured by Letters Patent, is

1. In draft-indicators for locomotive-furnaces in which the draft isaccelerated by the intermittent action of exhaust steam, the combinationof a transparent U gage,a chamber arranged alongside the gage, a tubularconnection between one leg of the gage and the chamber, a Valvesuspended to hang across the passage for checking or preventingpulsations in the gage incident to intermittent exhaust, and asuction-pipe leading from chamber to lire-box, substantially asdescribed.

2. In a locomotive-engine having exhaust mechanism adapted to dischargethrough or at one side of the stack, and means for regulating thedischarge from the cab of the engine, the combination with such engine,of a visual indicator consisting of a transparent U gage, avalve-chamber communicating with one leg of the gage, a suspended flatvalve for preventing pulsations in the gage, and a suction-pipeextending from valvechamber to fire box of the engine, substantially asdescribed,

In testimony whereof I aiiix my signature in presence of two witnesses.

JAMES EARLE RANKINE.

lVitnesses:

JAMES HYATT, E. V. HYATT.

